As is generally well known in the art, pressure transducers are employed for sensing a monitored fluid pressure and in response thereto providing an electrical signal to an associated electrical or electronic circuit.
By way of example, in the automotive industry it is accepted practice to employ pressure transducers for monitoring the pressure of the engine oil of an automotive engine. Usually, in such arrangements, the pressure transducer is situated as to monitor the pressure of the pumped engine oil, as at a point upstream of the related engine oil pump, and in response to the sensed magnitude of the monitored oil pressure produce an electrical signal or output which, in turn, is applied to an electrical read-out gauge located as on the instrument panel of the associated vehicle to thereby advise the operator of such vehicle as to engine oil pressure as well as the insufficiency thereof.
A problem has developed in the use of pressure transducers, as described, in that some automotive engines, especially of the internal combustion piston type, exhibit an operating characteristic which, in the main, is incompatible with the pressure transducer producing a useful electrical signal or output to the related electrical read-out gauge.
More particularly, it has been found that, for example, a manufacture of engines may specify, as to a manufacturer of pressure transducers, that the pressure transducer to be supplied for a particular engine must operate accurately (i.e., produce accurate and reliable electrical output signals) even if the magnitude of the engine oil pressure has pulsations in the range of 4.0 p.s.i. However, when the pressure transducer, designed for such a specified range of engine oil pulsations, is operatively connected to the engine, the output of the pressure transducer is unstable and unreliable. In such situations it has been found that the actual range of engine oil pulsations is actually much greater than that originally believed and specified.
Such pressure transducers, as is well known in the art, comprise a passage or passage means which serves to communicate as between a pressure responsive and movable wall means, and the like, within the transducer, and a source of the engine oil, under pressure, being monitored. One way of overcoming the problem, of an increased or excessive range in magnitude of engine oil pulsations, would be to further constrict the cross-sectional flow area of the transducer's passage means communicating with the source of pressurized engine oil. However, to do that would make such transducer passage means much more vulnerable to becoming blocked as by foreign particles which may be carried by the engine oil thereby effectively rendering the pressure transducer inoperative. Further, it is not unusual for an engine manufacturer to specify the acceptable minimum cross-sectional flow area of such transducer passage means. The establishment of such an acceptable minimum cross-sectional flow area, in turn, often prevents the pressure transducer manufacturer from being able to sufficiently constrict the transducer passage means in order to sufficiently damp the engine oil pulsations.
Accordingly, the invention as herein disclosed is primarily directed to the solution of the aforestated as well as other related and attendant problems of the prior art.